Evaluation of ³H-Paroxetine as a Radioligand for in vivo Study of 5-Hydroxytryptamine Uptake Sites in Mouse Brain

Abstract

The distribution of radioactivity in the mouse brain after intravenous administration of ³H-paroxetine was in the order (highest to lowest) hypothalamus>cerebral cortex>cerebellum. The radioactivity in the hypothalamus and cerebral cortex after injection of ³H-paroxetine was significantly decreased by treatment with 6-nitroquipazine or paroxetine. HPLC and TLC analyses show that no radioactive metabolites were found in the mouse brain 3 h after intravenous administration of ³H-paroxetine. The present results indicate that ³H-paroxetine would be a suitable radioligand for in vivo study of 5-HT uptake sites in mouse brain.